Опция 1 Использование findIndex
const arr = [["a","b"],["f","r"],["r",22,"t"]];
console.log(arr.findIndex(a => a.includes(22)));
Опция 2 : использование функций indexOf и включает :
const arr = [["a","b"],["f","r"],["r",22,"t"]];
// find element
const element = arr.find(a => a.includes(22));
// find element index
const currentIndex = arr.indexOf(element)
console.log(currentIndex);